About COVID-19

It currently takes 4-7 business days to get the results from a COVID-19 test.  Depending on your testing location, a Marin County Public Health Nurse or your doctor will call you with your test results. 

While you are waiting on your results, you must self-quarantine:

  • Do not leave your home:  Except for a medical emergency, you should not leave your home.  A household member or friend should handle any outside activities that are allowed under the shelter-in-place order, such as grocery shopping.
  • Quarantine yourself to a small space in your home: If possible, designate a room and bathroom that only you will use until you know your test results.  The smaller the area, the easier it will be to disinfect it properly.

For detailed guidance see Post-Test Isolation Guidance.

If you test positive, a Marin County Public Health representative will contact you to conduct a contact tracing investigation.  This investigation identifies any close contacts who are at high risk of exposure and will need to isolate from others and be tested for COVID-19.

Learn more about COVID-19 testing in Marin County by visiting our Testing Information webpage.

Last Updated 07/14/2020 - 13:25

A comprehensive glossary of public health and epidemiology terms can be found at the Kaiser Family Foundation’s website.


 Source: Kaiser Family Foundation

Last Updated 04/10/2020 - 20:09

The virus is thought to spread mainly from person-to-person between people who are in close contact with one another (within about 6 feet). This occurs through respiratory droplets produced when an infected person coughs or sneezes. These droplets can land in the mouths or noses of people who are nearby or possibly be inhaled into the lungs.  This is similar to how influenza and other respiratory pathogens spread.


It may be possible that a person can get COVID-19 by touching a surface or object that has the virus on it and then touching their own mouth, nose, or possibly their eyes. This is not thought to be the main way the virus spreads, but we are still learning more about this virus. People are thought to be most contagious when they are most symptomatic (the sickest).  People can also be contagious before they show symptoms.


The best way to prevent the spread of COVID-19 is to:

  • frequently wash your hands for at least 20 seconds
  • clean and disinfect surfaces – particularly those that people frequently touch
  • social distance by staying at home as much as possible and remaining at least 6 feet away from others when not at home
  • Cover your mouth and nose with a cloth face cover when you go out in public
  • Remember to cover your cough or sneeze, then throw away used tissues and wash your hands
  • isolate yourself if you have symptoms or were in close contact with a person who has COVID-19.


Source:  CDC

Last Updated 04/10/2020 - 19:56

There are a number of factors that determine how serious a disease is:  

  • R0 Number:  an estimate of how many people will be infected by a person with the disease 

  • Incubation time: the time from when a person was exposed to the disease and when they first show symptoms.  People can still transmit the disease to others during this time without even knowing they are sick. 

  • Hospitalization Rate: the percentage of people with the disease who will have severe illness that requires hospitalization.  

  • Case fatality rate: the percent of people with the disease who will die of it.  

To understand how serious COVID-19 is, it can be helpful to compare it to seasonal flu based on what we currently know about COVID-19:  




RO Number 


2 – 2.5 

Incubation Time 

1-4 days 

1 – 14 days 

Hospitalization Rate 



Case Fatality Rate: 

.1% or less 

1 – 3.4% 

Sources:  CDC, WHO, NCBI 

Last Updated 04/10/2020 - 19:38

Coronaviruses are a large family of viruses. Some cause illness in people, and others, such as canine and feline coronaviruses, only infect animals. Rarely, animal coronaviruses can cause animal-to-person infection.  If that happens, there is a risk that the virus can then spread person-to-person.   

We suspect this occurred for the virus that causes COVID-19. Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS) are two other examples of coronaviruses that originated from animals and then spread to people. 

Source:  CDC.gov 

Last Updated 04/10/2020 - 19:59

Novel simply means new, so novel coronavirus is the new virus from the coronavirus family. The official name of the virus is severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) but that name is rarely used.

COVID-19 is the disease caused by the novel coronavirus SARS-CoV-2.

Source: World Health Organization

Last Updated 04/10/2020 - 20:02

Coronavirus disease 2019 (COVID-19) is a respiratory illness that can spread from person-to-person. The virus that causes COVID-19 is a novel coronavirus, meaning that is has not been previously identified so people have no immunity to it.   

Source:  CDC.gov 

Last Updated 04/10/2020 - 19:57

Unless your work is exempted in the Order, you cannot go to work at a physical location in the County even if you want to.  You can work from home for any business if your employer allows it and your work can be done from home. It is important that we all do our part in stopping COVID-19 – staying home is an important part of that.

Last Updated 04/10/2020 - 21:08

Currently, there is no specific antiviral treatment for COVID-19. People with COVID-19 can seek medical care to help relieve symptoms. 

Patients who are confirmed to have COVID-19 will be cared for by healthcare professionals. Healthcare professionals will decide if a person ill with COVID-19 requires hospitalization or if home isolation is appropriate. That decision may be based on multiple factors including severity of illness, need for testing, and appropriateness of home for isolation purposes.

Care at home includes bed rest, fluids, and over the counter fever-reducing medicine. The ill person must stay away from other people and pets in their home (home isolation).

Source:  CDC, Marin County HHS

Last Updated 04/10/2020 - 19:53

There is currently no vaccine to prevent COVID-19. Although scientists are currently working on a vaccine, the process is complex and could take months or years. The best way to prevent illness is to avoid being exposed to this virus and taking measures to protect yourself.

Last Updated 04/10/2020 - 19:54

People may be sick infected with the virus for 1 to 14 days before developing symptoms. The most common symptoms of COVID-19 are:

  • fever
  • tiredness
  • dry cough
  • shortness of breath

Most people (about 80%) recover from the disease without needing special treatment. However, if you develop emergency warning signs for COVID-19 get medical attention immediately. Emergency warning signs include*:

  • Trouble breathing
  • Persistent pain or pressure in the chest
  • New confusion or inability to arouse
  • Bluish lips or face

*This list is not all inclusive. Please consult your medical provider for any other symptoms that are severe or concerning. 

CDC, World Health Organization

Last Updated 05/22/2020 - 12:22

There are many types of coronavirus. Some are common and usually mild like the common cold. Others are more severe like SARS (Severe acute respiratory syndrome). A novel coronavirus is a new coronavirus that has not been previously identified. It means that people have no immunity (or protection) against the disease it causes. This novel coronavirus was identified in December 2019. The disease it causes is called COVID-19 (coronavirus disease 2019).

Source: CDC.gov

For more information: see information about 2019 Novel Coronavirus on the Centers for Disease Control and Prevention (CDC) website

Last Updated 04/10/2020 - 15:21